This invention relates generally to improvements in machines and systems for use in cleaning carpets and upholstery and the like. More specifically, this invention relates to an improved cleaner unit having an adjustable power control so that electrical power usage can be variably set in accordance with available circuit capacity.
Carpet and upholstery cleaning systems and related equipment are, in general, relatively well-known in the art. Such systems commonly include a solution tank for receiving a supply of a selected cleaning fluid, in combination with a pump and related flow lines for delivering the cleaning fluid to an appropriate cleaning tool or head. The cleaning tool is normally designed for manual manipulation over a selected region of carpet or upholstery to be cleaned. In this regard, the cleaning action is typically enhanced by preheating the cleaning fluid with one or more electrical resistance heating elements. In addition, power-driven brush or vibratory elements can be provided on the cleaning tool to enhance the cleaning action. At the conclusion of a cleaning procedure, a vacuum motor is typically employed to vacuum excess fluid and entrained debris from the carpet or upholstery. All of these equipment components are frequently provided in a convenient portable form carried on a cart for easy transport directly to a site of use.
A typical cleaner unit for carpet and upholstery, as described generally above, thus includes multiple electrical loads which must be connected to an electrical power supply at the site of use. In a typical residential environment, the current capacity of a standard domestic household power circuit can vary within a significant range, typically on the order of 10 to 30 amps, depending upon the size rating of the fuse or circuit breaker associated therewith and other household loads which may be in operation when the cleaning unit is used. In this regard, modern carpet and upholstery cleaning units are commonly designed for optimum operational speed and efficiency, particularly by providing one or more resistance heaters so that a cleaning fluid can be heated rapidly and maintained at a desired elevated temperature for improved cleaning. In many cases, however, the total power requirements of the cleaner unit can exceed the available current capacity of a typical household power circuit, resulting in frequent tripping of circuit breakers and/or blowing of fuses, with corresponding delays in completion of the cleaning task. Such delays are, of course, particularly undesirable to professional cleaning services that schedule several cleaning procedures at different locations throughout the course of a typical work day.
In the past, to avoid undesirable tripping of circuit breakers and/or blowing of fuses, many portable cleaner units have been designed for reduced power usage typically by providing smaller resistance heaters which take longer to heat the cleaning fluid. Other cleaner unit designs have used multiple resistance heaters adapted for separate on-off operation, so that additional heaters can be turned on when the available circuit capacity is present.
The present invention provides further improvements in carpet and upholstery cleaner units, wherein one or more adjustable power controls can be variably set in association with one or more unit loads, so that the cleaner unit can be operated at maximum power level consistent with household circuit capacity.